DESCRIPTION

The pthread_kill() function sends the signal sig to thread, a thread in the same process
as the caller. The signal is asynchronously directed to thread.
If sig is 0, then no signal is sent, but error checking is still performed.

RETURNVALUE

On success, pthread_kill() returns 0; on error, it returns an error number, and no signal
is sent.

CONFORMINGTO

POSIX.1-2001, POSIX.1-2008.

NOTES

Signal dispositions are process-wide: if a signal handler is installed, the handler will
be invoked in the thread thread, but if the disposition of the signal is "stop",
"continue", or "terminate", this action will affect the whole process.
The glibc implementation of pthread_kill() gives an error (EINVAL) on attempts to send
either of the real-time signals used internally by the NPTL threading implementation. See
nptl(7) for details.
POSIX.1-2008 recommends that if an implementation detects the use of a thread ID after the
end of its lifetime, pthread_kill() should return the error ESRCH. The glibc
implementation returns this error in the cases where an invalid thread ID can be detected.
But note also that POSIX says that an attempt to use a thread ID whose lifetime has ended
produces undefined behavior, and an attempt to use an invalid thread ID in a call to
pthread_kill() can, for example, cause a segmentation fault.

SEEALSO

COLOPHON

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